Unquiet Spirit

St Thomas' College, Cambridge, has a ghost: or so some people believe. So when the Psychic Investigation Unit is summoned and a professor collapses with a heart attack during the proceedings, the college really is in a fix. Nathaniel Gye is called in to make discreet investigations. As he tries to tease out the twisted strands of this strange affair, anonymous letters arrive claiming that this unquiet spirit did not commit suicide 10 years ago but was murdered.